Boiler-furnace



Patented Nov. 3, 1885.

(No Model.)

0. B. DAVISON.

BOILER FURNACE.

oooooooo oooooooo o o o o NITED STAT S CHARLES B. DAVISON, OF ANN ARBOR,MICHIGAN.

BOlLER-FU RNAC E.

SPECIFICATION forming part of Letters Patent No. 329,539, dated November3, 1885.

Application filed May 12, 1885. Serial No. 165,216. (No model.)

To ml whom it may concern:

Be it known that 1, CHARLES B. DAVISON, a citizen of the United States,residing at Ann Arbor, in the county of \Vashtenaw and State ofMichigan, have invented certain new and useful Improvements inBoiler-Furnaces, of which the following is a specification, referencebeing had therein to the accompanying drawings.

My invention relates to an improvement in steam-boiler furnaces; and itconsists in the construction and arrangement of the parts more fullyhereinafter described, and pointed out in the claims.

The object of my invention is to obtain a more perfect combustion offuel than has hitherto been accomplished without material change oralteration of the furnaces now in use and by means simple andinexpensive in constructionIand readily understood and operated.

A further object of my invention is to consume the smoke and other gasesarising from combustion, thereby doing away with the obnoxious odors andthe inconveniences resulting therefrom, and at the same time securing agreat saving in the consumption of fuel.

Many attempts have been made to accomplish these objects, and by avariety of means and methods, but so far as I have been able to learnwith only partial success. The failure so to do has been due to the factthat certain necessary conditions have not been 'observed, and also thatthe means or methods employed have been complicated and cumbersome ordifficult to operate or carry out.

To secure perfect combustion, the following conditions must be observed,viz: First, the furnace must be supplied with a sufficient quantity ofair to furnish the needed oxygen; second, this air must be thoroughlymixed with the products of combustion arising from the bed of fuel;third, the gases arising from combustion must be kept at a high degreeof heat-not less than 800 Fahrenheit. These conditions may be maintainedby my improvement with ease and entire uniformity, and when somaintained perfect or nearly perfect combustion is secured.

I attain these objects by the means shown in the accompanying drawings,forming apart of this specification, wherein like letters of referenceindicate similar parts, and in which- Figure 1 is a longitudinalvertical section ofa furnace, and a side elevation of a part of aboiler, showing the steam-chamber and pipes for conducting the steam tothe furnace. Fig. 2 is a front elevation of a furnace and boiler,showing the arrangement and connections of the steam-pipes and theair-inlets in the furnace-doors; and Fig. 3 is a longitudinal verticalsection of a nozzle for the steam-pipes in the furnace.

A represents a steam-boiler set over a furnace and provided with asteam-dome, B. 0 represents the front wall of the furnace, and D thebridge-wall, between which walls the fire-grate E is supported. Thedoors I I are hinged in the usual manner and slotted or perforated, asshown at K in Fig. 2, for the purpose of admitting a current of air intothe furnace just over the surface of the fuel. These perforations orslots may be closed in whole or in part by suitable registers, asdesired. A pipe, F, connected with the dome B or the top of the boiler,or any pipe from the top is brought down in frontof the furnace, whereit joins a distributing-pipe, G, connecting with branch pipes H H, forconducting steam into the furnace. The pipes H H are placed over thedoors, and are bent at right angles near the ends, and carried throughthe front wall, the ends projecting through the wall be ing bent at suchan angle as to cause the steam forced through them to come in contactwith the current of air coming in through the slots or perforations K K,about two-thirds of the distance back from the front end of the furnace.The ends of said pipes are screw-threaded, on which are screwed thenozzles J. The nozzle J is about one and one-half inch long andthree-fourths of an inch in diameter at the largest end. It has athroat, 2, from one-sixteenth to one twenty-fourth of an inch indiameter. The throat is reduced in diameter, so that the jet or currentof steam can be more perfectly regulated. The mouth 3is hollowed out 'sothat the jets of steam may spread out and form a sheet reaching from oneside of the fire-chamber to the other. By means of this nozzle the steamis brought into the fire-chamber with such force as to thoroughlyagitate doors.

the gases arising from combustion and mix them with the incoming currentof air. The force imparted to said gases also carries them back alongthe bottom of the boiler, thus distributing the heat more uniformly, andat the same time greatly increasing the draft. The pipe F is providedwith a cock, L, for letting on and shutting ofi the steam.

The operation of my invention is as follows: The fuel on the gratehaving been brought to an incandescent state, a current of air isbrought into the fire-chamber through the slots or perforations in thedoors I I, just above the level of the fuel. The cock L having beenturned, jets of steam are forced into said chamber through the nozzles JJ at such an angle as to strike the current of air about twothirds thedepth of the furnace back from the The air being heated by passing overthe incandescent fuel gives off its oxygen, which, becoming thoroughlymixed with the gases arising from combustion by the jets of steam, therequisite amount of oxygen is brought in contact with said gases and theunconsumed particles of carbon to insure complete combustion. The forceof the jets of steam is such as to drive the heat in the firechamberback under the boiler, and thereby better distribute the same. The fineparticles of carbon being-consumed, the flues are not clogged thereby.The draft is greatly improved by the force of the steam, thereby aidingin the distribution of the heat. 1

The advantages of my invention are, first, simplicity and cheapness ofconstruction and operation; second, the facility with which it can beadapted for furnaces nowin use; third, its durability; fourth, thesaving of fuel and consumption of smoke and other gases; fifth, the useof cheaper grades of coal is by it made possible and profitable.

Having thus described my invention, what I claim, and desire to secureby Letters Patent, is-

1. In a steam-boiler furnace, the combination of doors having slots orperforations about on a line with the upper surface of the fuel, asdescribed, for the admission of air into the fire-chamber, withsteanrpipes having distributing-nozzles set at such an angle that thesteam forced therethrough will strike the current of air coming inthrough the doors at a point about two-thirds the distance back fromsaid doors, substantially as described.

2. In a steam-boiler furnace, the combina tion of a pipe leading fromthe steamrdome and one or more branch pipes provided with nozzlesextending into the fire-chamber at such an angle as to bring thecurrents or jets of steam in contact with the air entering through slotsor perforations in the doors, about on a line with the upper surface ofthe fuel, and

the gases arising from combustion, about twothirds the distance backfrom the doors, substantially as described.

3. In a steam-boiler furnace. the combination of slotted or perforateddoors, as described, steam pipes entering the furnace through the frontwall at such an angle that the steam will come in contact with a currentof air coming in through slots or perforations in the doors, about on aline with the upper surface of the-fuel and the incomplete products ofcombustion arising from the fuel,

about twothirds of the depth of the furnace

